Current seal designs are made with a non-elastomeric element which, under tension, takes a permanent set consequently losing the initial interference with the splined teeth. Further, an expensive thread operation is provided on these designs in order to hold the seal in position on the housing. However, the metal to metal threads do not provide for a positive seal between the seal and the housing. This type of previous seal is also easily damaged during installation and one or more of the component parts can become lost due to the loose assembly. These current dust cap seals are three piece seals consisting of: (1) an outer case, (2) an inner retainer ring with the approximate shape of the splined teeth, and (3) the sealing element itself, which is usually cork or felt material. This type of seal offers very little sealability due to the materials used and the construction of the sealing areas. The three piece construction affects the assembly operation by making it more difficult and leak paths can occur through the mating surfaces of the constructed pieces. Lip type seals are also used in splined shaft applications, however, they cannot seal in the splined area so they are limited in use to a smooth surface adjacent to the splined area. In most applications, the splined section of the shaft must pass through the lip of the seal during installation and this can result in damage to the seal.
It is an object of the present invention to provide an improved splined shaft seal that overcomes the problems mentioned above that are inherent in the prior art seals. It is a further object of the present invention to provide a splined shaft seal having an elastomeric element that is not easily damaged during installation and that is designed to either press on or screw on the spline housing without having first been pushed over the splined shaft. It is another object of the present invention to provide such a seal having elastomeric teeth adapted to mate with the grooves in the splined shaft and having an interference that provides proper sealing. It is another object of the present invention to provide a positive seal between the seal and the housing through which the splined shaft extends.